Highly sensitive potentiometric sensor for detection of mercury in Cl−-rich samples

Abstract

a b s t r a c tPotentiometric sensors have been exploited for the determination of Hg 2+ ions. However, applications of such sensors are limited to mercury detection in the absence of a Cl − -rich background since Hg 2+ can readily form coordination complexes with Cl − . This paper describes a potentiometric sensor for the determination of anionic mercury species using tert-butylcalix[4]arene-tetrakis(N,N-dimethylthioacetamide) as anion-selective ionophore and tridodecylmethylammonium chloride as ion exchanger. An asymmetric membrane rotating ion-selective electrode configuration is used to improve the detection sensitivity. By using HgCl 3 − as a model of anionic mercury species, the proposed method allows potentiometric detection of mercury down to nanomolar levels in samples containing 0.05 M NaCl background electrolyte. The practical application of the proposed sensor has been performed for the determination of total mercury concentrations in diluted seawater samples.

Electroanalysis with Membrane Electrodes and Liquid–Liquid Interfaces

“…While the technical quality of the paper is not very high and the detection limits were likely biased with the 0.1 M Hg­(II) solution used as inner electrolyte, the lifetime and selectivity of the membrane appear to be promising. On the other hand, Qin and co-workers showed that membranes containing the commercially available Lead ionophore IV are responsive to the HgCl 3 – species, allowing its detection in chloride rich media . While this anion is already rather lipophilic, the selectivities were significantly improved relative to those using membranes containing anion-exchanger only, with chloride discriminated against by nearly 9 orders of magnitude.…”

Polymeric membrane ion-selective electrodes with anti-biofouling properties by surface modification of silver nanoparticles

“…Nowadays, polymeric membrane ion-selective electrodes (ISEs) have become a powerful analytical tool in a variety of fields [1][2][3][4][5]. Especially in environmental monitoring, such electrodes play an important role in real-time and accurate analysis of some environmental parameters, such as pH, the concentrations of Ca 2+ , NH 4 + , and carbonate [6][7][8].…”

Potentiometric detection of glucose based on oligomerization with a diboronic acid using polycation as an indicator

“…A rotating silver disk electrode (ATA-1B, Jiangsu Jiangfen Electroanalytical Instrument Co., Ltd., China) with a diameter of 3 mm was used as internal reference electrode as described before to obtain more stable and reproducible potential responses. 36 All experiments were performed with a rotating mode conguration (at 3000 rpm). All electromotive force (EMF) values were measured using a Model CHI 760C electrochemical workstation (Shanghai Chenhua Apparatus Corporation, China) in a Faraday cage in the following galvanic cell: saturated calomel electrode (SCE)/0.1 M LiOAc/sample solution/sensing membrane/inner lling solution/AgCl/Ag.…”